Plaintiff corporation appealed from judgment affirming administrative decision of IDOR denying corporate tax refund, based on corporation's request to carry back net capital loss suffered by parent company, to offset capital gain Plaintiff had previously reported. Even if apportionment of net capital losses, solely for carry-back purposes, was not computed in same manner as net capital gains, that differentiation is consistent with IDOR regulations governing apportionment of gains as losses. That use of combined apportionment method to allocate losses would change tax liability for 1999 does not mean that use of IDOR's method is unconstitutionally disproportionate or caused gross distortion in its income attributable to Illinois. (McBRIDE and TAYLOR, concurring.)